Lenovo offers a [https://download.lenovo.com/consumer/mobiles_pub/lenovo_a3500_hmm_en_20140303.pdf|Hardware Maintenance Manual] that has instructions for disassembling the tablet. They do not go into detail about removing the cracked LCD or digitizer. I did find a videos on Youtube.
If the digitizer works and is not cracked, you can view [https://www.youtube.com/watch?v=EwonakFrFX4|Wymiana wyświetlacza LCD w tablecie LENOVO PAD - repair - dissasembly], that goes into detail of replacing the LCD only.
You can [https://support.lenovo.com/us/en/supportphonelist|contact] Lenovo to see about the specific part number for the LCD. On page 68 of the Hardware Maintenance Manual, it list part number 50100530 for the front module, which I believe consist of the digitizer and LCD. They may or may not sell the LCD separately.